As for wind measurement with a laser radar device, the laser radar device radiates laser pulse light into the atmosphere as transmission light and receives scattered light (reflected light) by aerosols as received light. Then, the laser radar device obtains a Doppler shift caused by the movement of the aerosols through heterodyne detection between the received light and the local light of the transmission light, which is continuous light with a single wavelength, and measures a wind speed in the radiation direction. The Doppler shift is calculated from a spectrum obtained by a Fourier transform of the signal after the heterodyne detection. In addition, the wind measurement direction is changed by switching the radiation direction of the transmission light (for example, see Patent Document 1).